Mold



July 24, 1928, 1,677,881

A. BAISH MOLD Filed May 13 1925 Jim/,1.

Patented July 24, 1928.

UNITED STATES ADRIAN BAISH, OI WADSWOB'IH, OHIO.

HOLD.

Application filed Kay 13, 1925. Serial 1103305105.

This invention relates in general to molds and more particularly to an improved rubber composition mold, the resent invention consisting in the novel mo (1 structure and 5 composition as well as in the novel process for producing the mold. 9

One of the principal objects of the present invention resides in the provision of a procem and mold of the character specified whereby a composition rubber mold may be produced in an easy and practical manner with comparatively slight ex ense and of. such a character as to enable t e production of various and sundry articles such as floor coverings, imitation leather, as well as other diverse articles from rubber compositions; all molded goods, such articles as toys, balls, heels, belts, small solid tires for baby buggies, trucks, coaster wagons, etc., in such a way that the imitation or composition arti cles have the features of pattern, ornamentation, external structure of similar articles of textile or leather, while being much less expensive to produce and of greater strength and durability.

Y A further object of the invention resides in the provision of a composition rubber mold which maintains its s ape and form under severe and prolonged use and which 3 may be readily reconditioned at a comparativel slight expense, and very light to ban le.

Other objects and advantages reside in certain novel features which W111. be herein- 35 after more fully described.

In the drawing accompanying the application:

Figure 1 is a view illustrating the manner of producing the mold; and

* Figure 2 is a view showing the mold structure.

In producing the mold constituting the present invention a mold bac or apron designated at 1 is first prepa Inpreparing this apron or backing the ordinary rubber mill or mixing machine used in the manufacture of rubber is employed.

I broug t closertogether in order to work the at right angles to the cords of theother, the

H The composition of the apron for backing isvas follows:

. f Part8. Smoked sheet 10 Crushed and disintegrated beads of old tires (fabric) Sulphur; Zinc oxide Magnesium oxide Dixie clay Black substance (oils and sulphur) An accelerator comprising a zinc salt of dimethyldithiocarbamic acid and aflsmall amount of methyl mustard 0 In place of the smoked sheet caoutchouc or a mixture of thelatter with palm oil may be employed; fifteen. parts of caoutchouc and five parts of palm oil being employed.

The beads are first crushed on the rolls of the rubber mill, then the smoked sheet or caoutchouc broken down on the mill 20 minutes and afterwards the other ingredients are thoroughly incor orated in a the mix. After the in redients ave been completely and thoroug lyincorporated, a layerof cord fabric is placed on the sheet of composition thus formed and the sheet and cords arerun through the mill one way with the mill 0 ened and each time the mill rolls are cords into the sheet until they are embedded in the sheet about half way from its opposite faces. a

This green stock is then placed on a stand just as it is taken from the mill, and left there until one wishes to. use it. When the mold is to be prepared two sections or pieces of; stock are taken from the stand and are laid one on the other with the cords of one same as crossing the grains.

On the backing thus constituted a previously repared mold facing is placed. The mol facing is of hard sponge rubber plastic when first placed on the back but fixed and hardened and united and vulcanized to the back or apron stock, and at the same time receiving the impression of the.

original. The mold facing may be of any one of the following compositions:

It is upon the mold facing that the or1g1- nal design is laced just before the apron and mold faclng are placed in the press. Both. mold facing and original must be dusted with wheat flour before being placed An accelerator comprising a zinc salt of dimethyldithiocarbamic acid and a small amount of methyl mustard oil- 2 Two.

Parts.

Smoked sheets 285 Sulphur 105' Tripoli 90. Lithoponeuc 150 to 250 Candelilla wax 2O Asbestine 20 Powdered mica 20 Magnesium carbonate 40 Lime 20 Sulphate of zine 40 Accelerator (as in one) 2 Three.

Parts.

Oil steamed shoddy 200 Cotton lints 100 Zinc oxide 100 Lime 50 Powdered coke 200 Powdered mica 100 Dixie clay 100 Murcurious 'nitrate 1 Sulphur 100 Carbon black 20 Accelerator (as in one) 1 An accelerator comprising an ethylidene m Q GHENH) T-QH-CHa (C H N..CH

(This accelerator is hereinafter referred to as accelerator No. 2.)

Part8.

Smoked sheets. 185 Sulphur 105 W'hiting 90 Zinc oxide 50 Lithopone 120 Cerecine wax 30 Asbestos pulp 40 Asbestine 20 Powdered mica n Magnesium carbonate 20 Accelerator (as in one) 1 Five.

' Parts Smoked sheets 10 Oil steamed shoddy 50 Sulphur 14 M. R. X ((mineral rubber) 1 Zince oxi e 3 Magnesium oxide 2 Dixie clay 17 Black substance 2% Accelerator No. 2 Lime 10 I The ingredients of the composition to be used and which may be any of the five just described are thoroughly incorporated in the mill and worked into a sheet-like form. Afterwards the mix is calendered into liner rolls to be stored for future use. The section to be used as mold facing is severed from the roll. and applied to and placed on the top layer of the backing as shown in drawings. In the drawings the facing is indicated at 2. The backing is larger than the facing and around the facing a frame is placed. The frame shown consists simply of a number of metallic bars which rest on the backing and engage the edges of the facing. The metallic bars are designated at 3.

The backing, facing and bars are then placed on the head 5 of a press and the original which may be a rug or any other article which the mold is to reproduce is placed on,

the facing. The facing is dusted evenly with flour, also the original before placing the original thereon. Then after the original is placed on the mold a heavy cotton cloth is placed over the top of the stock to hold the heat. The press is operated to cause its heads 5 and 5 to come together with the assembled mold parts, original and cloth between them and steam is supplied to the hollow heads of the press so as to subject the mold facing and backing to the action ofheat and pressure which causes the 2 original 'ta"'im ress' the mold facing and which cures or vulcanizes the backing and facing so that the backing and facing are welded or united or vulcanized or adhesion takes place permanently and the-mold is fixed and hardened and at the "same time having received the impression. Of course, it

is understood that the heat treatment on the press isthe first to which the backing or-fac- 'ing issubjected, the rolls'of the mill being kept cool during the preparation of breaking down and mixing the stock on the mill.

The backing with its two series of angularly exposed cords is inextensible and willnot spread in the press. The facingis held against spreading by the action of the bars 8 while in. the .press' and after the facing-- 1 and backing are permanently united and. vulcanized, the facing ishardened andfixed and is strengthened by the. inextensible ln'using' the mold with the compositions which make up the articles to "be produced; the face of the mold is dusted with wheat flour or with refined corn meal flour, also i .article is dusted, to facilitate stripping of mold. Many varied and'diverse articles may of cylindrical formto provide rollers adaptfed for use in various -arts, an 'exampleof .which use isthe ornamenting, figuring, or

the articles from the mold. The articles .to be produced are made of-a composition ineluding rubber and must be: stripped immediatelyrafter removal from the vulcanizing press in which they are placed with-the be producedin this way. a w

If the mold facingis ofthe composition specifiedunder the heading One, the mold facing and'backingand-the original are kept in the press for a period ranging from sixty. to seventy minutes WllllG steam pressure.

amounting to seventy pounds is, supplied'to th'ejhollow head of the press. The composi;

tion definedun der heading Two requires.

the same cure; The composition defined.

underheading Three must be keptin the press for fortyfi've minutes with aysteam pressure ofeigh'ty pounds, the 'composltion defined under heading .-F our for sixty. minutes with forty pounds steam pressure; and the composition defined under -heading Five for fifteen: minutes with eighty pounds steam pressure. 4

The usualform of the mold is flat, but it may beshaped as desired, and may be made embossing of imitation leather.

. The mold produced by the invention is p'hrin'carrier, compr slng a 'zinc salt of diof asbestos.

's'ium,=acompound of zinc, lime, anda'form.

form ofasbestos. a

7. Acomposition mold facing consisting of a Y jli'me and a form of asbestos.-

' comparatively inexpensive to manufacture,

may be impressed from practically any original, permits the articles which it shapes and forms'to be. readily stripped therefrom and stands up under prolonged and severe uses. The mold can be used. for as many 'cures asthe person desires.

There must be metallic bars used about the mold eachcure in order to hold the stock from runningout over the mold. The stock mentioned is that which is being cured into the; same design asthe mold or original design.

-. I clai'nii 1. A composition mold facing consisting of. rubber, sulphur an accelerator or sul-- methyldithiorcarbomic acid and a small 24A composition mold facing consisting of rubber, sulphur,- an accelerator or. sulphur carrier, a compound'of magnesium, acomamount of methyl mustard oil, a fillerand lightener, and a drier.-

", pound of zinc, lime, and a form of asbestos.

3. A composition mold facing consisting of rubber, sulphur, an accelerator or sulphur" carr1er,-- a compound of, 'z1nc,lnne and'a form A composition mold facing consisting of'ru'bber, sulphur, an accelerator or sulphur *cariier, a compound of magnesium,lim'e,- -and a form ofasbestos.

' 5'. A composition mold facing'consisting of. rubber," sulphur, an accelerator or su'l-.

phur carrier, a wax, a compound. of magnev of asbestos.

rubber, sulphur, an accelerator or sulphur carrier, a wax, lithopone, a. compound of.

magnesium, a compound of zinc, lime anda rubber, sulphur, an .acceleratoror sulphur v 6. A composition mold facing consisting of carrier, tripoli, a wax, lithophone, a compound of magnesium, a compound of zinc, 

